Communications Device and Method in High-Frequency System

ABSTRACT

A communications device in a high-frequency system, including: a scan module, configured to use a single beam for each space S region in a to-be-scanned sector of a cell to poll or cover all time T regions in the S region in a time-division manner, and send a synchronization sequence to user equipment in the T region by using a preset frame structure; and a determining module, configured to receive a sequence that is fed back by the user equipment, determine a location of the user equipment according to the sequence, and determine, according to the location of the user equipment, a serving beam for a base station to communicate with the user equipment, to confirm that scanning for the user equipment is completed. The embodiments of the present invention further provide a scanning method in a high-frequency system.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/CN2014/083053, filed on Jul. 25, 2014, the disclosure of which ishereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates to the field of communicationstechnologies, and in particular, to a communications device and methodin a high-frequency system.

BACKGROUND

As mobile terminals increase, a demand of a user for a data volumeincreases. Currently, bandwidth provided for a lower frequency band isinadequate to meet ever growing demands for communication performance.Therefore, using high frequencies (30 G to 300 G or higher) havingabundant bandwidth resources as a backhaul frequency and an accessfrequency will become a trend. Compared with the lower frequency band, ahigh frequency band has one significant feature, a narrower beam. Ifuser access is implemented by using a high-frequency narrow beam insteadof a conventional low-frequency wide beam, a signal coverage (that is,signal scanning) area of a base station is reduced significantly. Inthis case, a relatively large quantity of beams are needed to implementcell-wide coverage of a base station signal. However, in an actualapplication, due to a restriction on beam freedom, one base station canemit only a limited quantity of beams, and a coverage area (that is,scan range) of each beam is limited. As a result, cell-wide coveragecannot be ensured.

In the prior art, access of multiple users is mainly implemented byusing a single beam in a time division manner. In a prior-art multi-useraccess process, a single beam is mainly used to implement full-rangetime-division scanning of a base station signal for multiple users. Whenthere are a large quantity of users evenly distributed within a coveragearea (for example, a cell), in the prior-art implementation manner inwhich a single beam is used to implement time-division scanning of abase station signal for multiple users, a waiting time for each user isrelatively long, and a throughput is reduced, resulting in poor userexperience when full coverage is implemented.

SUMMARY

Embodiments of the present invention provide a communications device andmethod in a high-frequency system, where when multiple beams are used, asingle beam may be used for each S region in a to-be-scanned sector toscan for user equipment included in all T regions in the S region, andsuccess in signal scanning for the user equipment is determinedaccording to a sequence that is fed back by the user equipment, therebyeffectively increasing a coverage rate of a base station signal in acell, shortening a waiting time for a user in the cell to receive thebase station signal, and improving user experience in cell-widecoverage.

A first aspect of the embodiments of the present invention provides acommunications device in a high-frequency system. The device may includea scan module, configured to use a single beam for each space S regionin a to-be-scanned sector of a cell to poll or cover all time T regionsin the S region in a time-division manner, and send a synchronizationsequence to user equipment in the T region by using a preset framestructure, where the frame structure is carried in a beam signal. Thedevice may also include a determining module, configured to receive asequence that is fed back by the user equipment, determine a location ofthe user equipment according to the sequence, and determine, accordingto the location of the user equipment, a serving beam for a base stationto communicate with the user equipment, to confirm that scanning for theuser equipment is completed.

With reference to the first aspect, in a first possible implementationmanner, the communications device further includes: a division module,configured to divide the to-be-scanned sector of the cell into multipleS regions according to a predefined S region division rule, and divideeach of the S regions into multiple T regions according to a preset Tregion division rule.

With reference to the first possible implementation manner of the firstaspect, in a second possible implementation manner, the S regiondivision rule includes: evenly dividing the to-be-scanned sector of thecell to divide the to-be-scanned sector into multiple equal-sized Sregions.

With reference to the first possible implementation manner of the firstaspect, in a third possible implementation manner, the S region divisionrule includes: dividing the to-be-scanned sector of the cell accordingto beam widths of beams emitted by the base station, to divide theto-be-scanned sector into multiple S regions whose sizes arecorresponding to the beam widths.

With reference to the second possible implementation manner of the firstaspect or the third possible implementation manner of the first aspect,in a fourth possible implementation manner, the division module isspecifically configured to: determine, according to a quantity of beamsemitted by the base station, a quantity M of S regions resulting fromdivision of the to-be-scanned sector, where each of the S regions iscorresponding to one beam, and M is equal to the quantity of beams; anddivide, according to the S region division rule, the to-be-scannedsector into M equal-sized S regions, or M S regions whose sizes arecorresponding to the beam widths.

With reference to the fourth possible implementation manner of the firstaspect, in a fifth possible implementation manner, the T region divisionrule includes: dividing all the S regions in a same division order todivide each of the S regions into multiple T regions.

With reference to the fourth possible implementation manner of the firstaspect, in a sixth possible implementation manner, the T region divisionrule includes: dividing different S regions in different division ordersto divide each of the S regions into multiple T regions.

With reference to the fifth possible implementation manner of the firstaspect or the sixth possible implementation manner of the first aspect,in a seventh possible implementation manner, the division module isspecifically configured to: determine, according to a beam width of abeam emitted by the base station and a size of the S region, a quantityN of T regions resulting from division of the S region; and divide eachof the S regions into N T regions in the same division order or adifferent division order according to the T region division rule.

With reference to the fourth possible implementation manner of the firstaspect or the seventh possible implementation manner of the firstaspect, in an eighth possible implementation manner, in the framestructure, each radio frame includes K1 equal-sized radio subframes,each of the radio subframes includes K2 equal-sized timeslots, and eachof the timeslots includes K3 OFDM symbols, where K1, K2, and K3 arepositive integers.

With reference to the eighth possible implementation manner of the firstaspect, in a ninth possible implementation manner, the scan module isspecifically configured to: insert M OFDM symbols into one downlinktimeslot in one radio subframe in the frame structure, insert thesynchronization sequence into the OFDM symbols, and send thesynchronization sequence to the user equipment in the T region by usingthe OFDM.

With reference to the ninth possible implementation manner of the firstaspect, in a tenth possible implementation manner, the synchronizationsequence includes a sequence ID of the beam that is emitted by the basestation to scan the T region; and the ID of the beam includes a cellsequence C_ID, a sector sequence SEC_ID, a space sequence S_ID, and atime sequence T_ID.

A second aspect of the embodiments of the present invention provides acommunications device in a high-frequency system. The device may includea receiving module, configured to emit a beam to perform beam signalscanning and receive beam signals transmitted by a base station. Thedevice may also include a processing module, configured to obtainsynchronization sequences from the beam signals received by thereceiving module, and correlate all the synchronization sequences. Thedevice may also include a selection module, configured to select asynchronization sequence whose correlation peak value is the largestamong correlation peak values that are of all the synchronizationsequences and that are obtained by means of processing by the processingmodule, and set a beam corresponding to the synchronization sequence asa serving beam. The device may also include a feedback module,configured to insert, into a specified orthogonal frequency divisionmultiplexing (OFDM) symbol, a sequence corresponding to an ID of theserving beam that is selected by the selection module, and feed back thesequence corresponding to the ID of the serving beam to the basestation.

With reference to the second aspect, in a first possible implementationmanner, each of the beam signals transmitted by the base station andreceived by the receiving module carries a preset frame structure; andin the frame structure, each radio frame includes K1 equal-sized radiosubframes, each of the radio subframes includes K2 equal-sizedtimeslots, and each of the timeslots includes K3 OFDM symbols, where K1,K2, and K3 are positive integers.

With reference to the first possible implementation manner of the secondaspect, in a second possible implementation manner, the OFDM symbols inthe frame structure of the beam signal include an ID of the beam, andthe ID of the beam includes a cell sequence C_ID, a sector sequenceSEC_ID, a space sequence S_ID, and a time sequence T_ID.

With reference to the second possible implementation manner of thesecond aspect, in a third possible implementation manner, thesynchronization sequence is carried in the OFDM symbols and thesynchronization sequence is corresponding to the ID of the beam in theOFDM symbols; and the processing module is specifically configured to:obtain the ID of the beam corresponding to the synchronization sequencefrom the OFDM symbols in the beam signal, and sequentially correlate theC_ID, SEC_ID, S_ID, and T_ID in the ID of the beam.

With reference to the third possible implementation manner of the secondaspect, in a fourth possible implementation manner, the feedback moduleis specifically configured to: select an OFDM symbol corresponding to aT_ID of the serving beam from OFDM symbols in an uplink timeslot; andinsert sequences corresponding to a C_ID, a SEC_ID, and an S_ID of theserving beam into the selected OFDM symbol, and feed back the sequencecorresponding to the ID of the serving beam to the base station by usingthe uplink timeslot.

With reference to the third possible implementation manner of the secondaspect, in a fifth possible implementation manner, the feedback moduleis specifically configured to: predefine an OFDM symbol in the uplinktimeslot; and insert sequences corresponding to a C_ID, a SEC_ID, anS_ID, and a T_ID of the serving beam into the predefined OFDM symbol,and feed back the sequence corresponding to the ID of the serving beamto the base station by using the uplink timeslot.

With reference to the fourth possible implementation manner of thesecond aspect or the fifth possible implementation manner of the secondaspect, in a sixth possible implementation manner, the sequencescorresponding to the C_ID, SEC_ID, S_ID, and T_ID of the serving beamare all predefined orthogonal sequences.

A third aspect of the embodiments of the present invention provides abase station. The base station may include a processor, configured touse a single beam for each space S region in a to-be-scanned sector of acell to poll or cover all time T regions in the S region in atime-division manner. The base station may also include a transmitter,configured to send, by using a preset frame structure, a synchronizationsequence to user equipment in the T region that is obtained by means ofprocessing by the processor, where the frame structure is carried in abeam signal. The base station may also include a receiver, configured toreceive a sequence that is fed back by the user equipment, where theprocessor is further configured to determine a location of the userequipment according to the sequence, and determine, according to thelocation of the user equipment, a serving beam for the base station tocommunicate with the user equipment, to confirm that scanning for theuser equipment is completed.

With reference to the third aspect, in a first possible implementationmanner, the processor is further specifically configured to divide theto-be-scanned sector of the cell into multiple S regions according to apredefined S region division rule, and divide each of the S regions intomultiple T regions according to a preset T region division rule.

With reference to the first possible implementation manner of the thirdaspect, in a second possible implementation manner, the S regiondivision rule includes: evenly dividing the to-be-scanned sector of thecell to divide the to-be-scanned sector into multiple equal-sized Sregions.

With reference to the first possible implementation manner of the thirdaspect, in a third possible implementation manner, the S region divisionrule includes: dividing the to-be-scanned sector of the cell accordingto beam widths of beams emitted by the base station, to divide theto-be-scanned sector into multiple S regions whose sizes arecorresponding to the beam widths.

With reference to the second possible implementation manner of the thirdaspect or the third possible implementation manner of the third aspect,in a fourth possible implementation manner, the processor isspecifically configured to: determine, according to a quantity of beamsemitted by the base station, a quantity M of S regions resulting fromdivision of the to-be-scanned sector, where each of the S regions iscorresponding to one beam, and M is equal to the quantity of beams; anddivide, according to the S region division rule, the to-be-scannedsector into M equal-sized S regions, or M S regions whose sizes arecorresponding to the beam widths.

With reference to the fourth possible implementation manner of the thirdaspect, in a fifth possible implementation manner, the T region divisionrule includes: dividing all the S regions in a same division order todivide each of the S regions into multiple T regions.

With reference to the fourth possible implementation manner of the thirdaspect, in a sixth possible implementation manner, the T region divisionrule includes: dividing different S regions in different division ordersto divide each of the S regions into multiple T regions.

With reference to the fifth possible implementation manner of the thirdaspect or the sixth possible implementation manner of the third aspect,in a seventh possible implementation manner, the processor isspecifically configured to: determine, according to a beam width of abeam emitted by the base station and a size of the S region, a quantityN of T regions resulting from division of the S region; and divide eachof the S regions into N T regions in the same division order or adifferent division order according to the T region division rule.

With reference to the fourth possible implementation manner of the thirdaspect or the seventh possible implementation manner of the thirdaspect, in an eighth possible implementation manner, in the framestructure, each radio frame includes K1 equal-sized radio subframes,each of the radio subframes includes K2 equal-sized timeslots, and eachof the timeslots includes K3 OFDM symbols, where K1, K2, and K3 arepositive integers.

With reference to the eighth possible implementation manner of the thirdaspect, in a ninth possible implementation manner, the transmitter isspecifically configured to: insert M OFDM symbols into one downlinktimeslot in one radio subframe in the frame structure, insert thesynchronization sequence into the OFDM symbols, and send thesynchronization sequence to the user equipment in the T region by usingthe OFDM.

With reference to the ninth possible implementation manner of the thirdaspect, in a tenth possible implementation manner, the synchronizationsequence includes a sequence ID of the beam that is emitted by the basestation to scan the T region; and the ID of the beam includes a cellsequence C_ID, a sector sequence SEC_ID, a space sequence S_ID, and atime sequence T_ID.

A fourth aspect of the embodiments of the present invention providesuser equipment. The user equipment may also include a receiver,configured to emit a beam to perform beam signal scanning and receivebeam signals transmitted by a base station. The user equipment may alsoinclude a processor, configured to obtain synchronization sequences fromthe beam signals received by the receiver, and correlate all thesynchronization sequences, where the processor is configured to select asynchronization sequence whose correlation peak value is the largestamong correlation peak values of all the synchronization sequences, andset a beam corresponding to the synchronization sequence as a servingbeam. The processor is configured to insert a sequence corresponding toan ID of the serving beam into a specified orthogonal frequency divisionmultiplexing OFDM symbol. The user equipment may also include atransmitter, configured to feed back the sequence corresponding to theID of the serving beam to the base station.

With reference to the fourth aspect, in a first possible implementationmanner, each of the beam signals transmitted by the base station andreceived by the receiver carries a preset frame structure; and in theframe structure, each radio frame includes K1 equal-sized radiosubframes, each of the radio subframes includes K2 equal-sizedtimeslots, and each of the timeslots includes K3 OFDM symbols, where K1,K2, and K3 are positive integers.

With reference to the first possible implementation manner of the fourthaspect, in a second possible implementation manner, the OFDM symbols inthe frame structure of the beam signal include an ID of the beam, andthe ID of the beam includes a cell sequence C_ID, a sector sequenceSEC_ID, a space sequence S_ID, and a time sequence T_ID.

With reference to the second possible implementation manner of thefourth aspect, in a third possible implementation manner, thesynchronization sequence is carried in the OFDM symbols and thesynchronization sequence is corresponding to the ID of the beam in theOFDM symbols; and the processor is specifically configured to: obtainthe ID of the beam corresponding to the synchronization sequence fromthe OFDM symbols in the beam signal, and sequentially correlate theC_ID, SEC_ID, S_ID, and T_ID in the ID of the beam.

With reference to the third possible implementation manner of the fourthaspect, in a fourth possible implementation manner, the processor isspecifically configured to: select an OFDM symbol corresponding to aT_ID of the serving beam from OFDM symbols in an uplink timeslot; andinsert sequences corresponding to a C_ID, a SEC_ID, and an S_ID of theserving beam into the selected OFDM symbol; and the transmitter isspecifically configured to: feed back the sequence corresponding to theID of the serving beam to the base station by using the uplink timeslot.

With reference to the third possible implementation manner of the fourthaspect, in a fifth possible implementation manner, the processor isspecifically configured to: predefine an OFDM symbol in the uplinktimeslot; and insert sequences corresponding to a C_ID, a SEC_ID, anS_ID and a T_ID of the serving beam into the predefined OFDM symbol; andthe transmitter is specifically configured to: feed back the sequencecorresponding to the ID of the serving beam to the base station by usingthe uplink timeslot.

With reference to the fourth possible implementation manner of thefourth aspect or the fifth possible implementation manner of the fourthaspect, in a sixth possible implementation manner, the sequencescorresponding to the C_ID, SEC_ID, S_ID, and T_ID of the serving beamare all predefined orthogonal sequences.

A fifth aspect of the embodiments of the present invention provides ascanning method in a high-frequency system, which may include: using, bya base station, a single beam for each space S region in a to-be-scannedsector of a cell to poll or cover all time T regions in the S region ina time-division manner, and sending a synchronization sequence to userequipment in the T region by using a preset frame structure, where theframe structure is carried in a beam signal; and receiving, by the basestation, a sequence that is fed back by the user equipment, determininga location of the user equipment according to the sequence, anddetermining, according to the location of the user equipment, a servingbeam for the base station to communicate with the user equipment, toconfirm that scanning for the user equipment is completed.

With reference to the fifth aspect, in a first possible implementationmanner, before the using, by a base station, a single beam for eachspace S region in a to-be-scanned sector of a cell to poll or cover alltime T regions in the S region in a time-division manner, the methodfurther includes: dividing the to-be-scanned sector of the cell intomultiple S regions according to a predefined S region division rule, anddividing each of the S regions into multiple T regions according to apreset T region division rule.

With reference to the first possible implementation manner of the fifthaspect, in a second possible implementation manner, the S regiondivision rule includes: evenly dividing the to-be-scanned sector of thecell to divide the to-be-scanned sector into multiple equal-sized Sregions.

With reference to the first possible implementation manner of the fifthaspect, in a third possible implementation manner, the S region divisionrule includes: dividing the to-be-scanned sector of the cell accordingto beam widths of beams emitted by the base station, to divide theto-be-scanned sector into multiple S regions whose sizes arecorresponding to the beam widths.

With reference to the second possible implementation manner of the fifthaspect or the third possible implementation manner of the fifth aspect,in a fourth possible implementation manner, the dividing theto-be-scanned sector of the cell into multiple S regions according to apredefined S region division rule includes: determining, according to aquantity of beams emitted by the base station, a quantity M of S regionsresulting from division of the to-be-scanned sector, where each of the Sregions is corresponding to one beam, and M is equal to the quantity ofbeams; and dividing, according to the S region division rule, theto-be-scanned sector into M equal-sized S regions, or M S regions whosesizes are corresponding to the beam widths.

With reference to the fourth possible implementation manner of the fifthaspect, in a fifth possible implementation manner, the T region divisionrule includes: dividing all the S regions in a same division order todivide each of the S regions into multiple T regions.

With reference to the fourth possible implementation manner of the fifthaspect, in a sixth possible implementation manner, the T region divisionrule includes: dividing different S regions in different division ordersto divide each of the S regions into multiple T regions.

With reference to the fifth possible implementation manner of the fifthaspect or the sixth possible implementation manner of the fifth aspect,in a seventh possible implementation manner, the dividing each of the Sregions into multiple T regions according to a preset T region divisionrule includes: determining, according to a beam width of a beam emittedby the base station and a size of the S region, a quantity N of Tregions resulting from division of the S region; and dividing each ofthe S regions into N T regions in the same division order or a differentdivision order according to the T region division rule.

With reference to the fourth possible implementation manner of the fifthaspect or the seventh possible implementation manner of the fifthaspect, in an eighth possible implementation manner, in the framestructure, each radio frame includes K1 equal-sized radio subframes,each of the radio subframes includes K2 equal-sized timeslots, and eachof the timeslots includes K3 OFDM symbols, where K1, K2, and K3 arepositive integers.

With reference to the eighth possible implementation manner of the fifthaspect, in a ninth possible implementation manner of the fifth aspect,the sending a synchronization sequence to user equipment in the T regionby using a preset frame structure includes: inserting M OFDM symbolsinto one downlink timeslot in one radio subframe in the frame structure,inserting the synchronization sequence into the OFDM symbols, andsending the synchronization sequence to the user equipment in the Tregion by using the OFDM.

With reference to the ninth possible implementation manner of the fifthaspect, in a tenth possible implementation manner, the synchronizationsequence includes a sequence ID of the beam that is emitted by the basestation to scan the T region; and the ID of the beam includes a cellsequence C_ID, a sector sequence SEC_ID, a space sequence S_ID, and atime sequence T_ID.

A sixth aspect of the embodiments of the present invention provides ascanning method in a high-frequency system. The method may includeemitting, by user equipment, a beam to perform beam signal scanning andreceive beam signals transmitted by a base station. The method may alsoinclude obtaining, by the user equipment, synchronization sequences fromthe beam signals, and correlating all the synchronization sequences. Themethod may also include selecting, by the user equipment, asynchronization sequence whose correlation peak value is the largestamong correlation peak values of all the synchronization sequences, andsetting a beam corresponding to the synchronization sequence as aserving beam. The method may also include inserting, by the userequipment, a sequence corresponding to an ID of the serving beam into aspecified orthogonal frequency division multiplexing OFDM symbol, andfeeding back the sequence corresponding to the ID of the serving beam tothe base station.

With reference to the sixth aspect, in a first possible implementationmanner, each of the beam signals transmitted by the base station carriesa preset frame structure; and in the frame structure, each radio frameincludes K1 equal-sized radio subframes, each of the radio subframesincludes K2 equal-sized timeslots, and each of the timeslots includes K3OFDM symbols, where K1, K2, and K3 are positive integers.

With reference to the first possible implementation manner of the sixthaspect, in a second possible implementation manner, the OFDM symbols inthe frame structure of the beam signal include an ID of the beam, andthe ID of the beam includes a cell sequence C_ID, a sector sequenceSEC_ID, a space sequence S_ID, and a time sequence T_ID.

With reference to the second possible implementation manner of the sixthaspect, in a third possible implementation manner, the synchronizationsequence is carried in the OFDM symbols and the synchronization sequenceis corresponding to the ID of the beam in the OFDM symbols; and theobtaining, by the user equipment, synchronization sequences from thebeam signals, and correlating all the synchronization sequencesincludes: obtaining, by the user equipment, the ID of the beamcorresponding to the synchronization sequence from the OFDM symbols inthe beam signal, and sequentially correlating the C_ID, SEC_ID, S_ID,and T_ID in the ID of the beam.

With reference to the third possible implementation manner of the sixthaspect, in a fourth possible implementation manner, the inserting, bythe user equipment, a sequence corresponding to an ID of the servingbeam into a specified orthogonal frequency division multiplexing OFDMsymbol, and feeding back the sequence corresponding to the ID of theserving beam to the base station includes: selecting, by the userequipment, an OFDM symbol corresponding to a T_ID of the serving beamfrom OFDM symbols in an uplink timeslot; and inserting, by the userequipment, sequences corresponding to a C_ID, a SEC_ID, and an S_ID ofthe serving beam into the selected OFDM symbol, and feeding back thesequence corresponding to the ID of the serving beam to the base stationby using the uplink timeslot.

With reference to the third possible implementation manner of the sixthaspect, in a fifth possible implementation manner, the inserting, by theuser equipment, a sequence corresponding to an ID of the serving beaminto a specified orthogonal frequency division multiplexing OFDM symbol,and feeding back the sequence corresponding to the ID of the servingbeam to the base station includes: predefining, by the user equipment,an OFDM symbol in the uplink timeslot; and inserting, by the userequipment, sequences corresponding to a C_ID, a SEC_ID, an S_ID, and aT_ID of the serving beam into the predefined OFDM symbol, and feedingback the sequence corresponding to the ID of the serving beam to thebase station by using the uplink timeslot.

With reference to the fourth possible implementation manner of the sixthaspect or the fifth possible implementation manner of the sixth aspect,in a sixth possible implementation manner, the sequences correspondingto the C_ID, SEC_ID, S_ID, and T_ID of the serving beam are allpredefined orthogonal sequences.

In the embodiments of the present invention, when multiple beams areused, a communications device may use a single beam for each S region ina to-be-scanned sector of a cell to poll or cover all T regions in the Sregion in a time-division manner, and send, by using a preset framestructure, a synchronization sequence to a user in a T region that isscanned by the single beam, to implement coverage of a base stationsignal for the user included in the T region. Further, thecommunications device may determine a location of user equipmentaccording to a sequence that is fed back by the user equipment, so as toaccess the user equipment and shorten a waiting time for each user toreceive the base station signal. This effectively improves a coveragerate of the base station signal for multiple users in the cell, improvesexperience of users in the cell, and reduces costs for cell-widecoverage.

BRIEF DESCRIPTION OF THE DRAWINGS

To describe the technical solutions in the embodiments of the presentinvention more clearly, the following briefly describes the accompanyingdrawings required for describing the embodiments. Apparently, theaccompanying drawings in the following description show merely someembodiments of the present invention, and a person of ordinary skill inthe art may still derive other drawings from these accompanying drawingswithout creative efforts.

FIG. 1 is a schematic structural diagram of a first embodiment of acommunications device in a high-frequency system according to theembodiments of the present invention;

FIG. 2 is a schematic diagram of a frame structure in a first embodimentof a communications device in a high-frequency system according to theembodiments of the present invention;

FIG. 3 is a schematic structural diagram of a second embodiment of acommunications device in a high-frequency system according to theembodiments of the present invention;

FIG. 4 is a schematic diagram of region division in a second embodimentof a communications device in a high-frequency system according to theembodiments of the present invention;

FIG. 5 is a schematic diagram of another region division in a secondembodiment of a communications device in a high-frequency systemaccording to the embodiments of the present invention;

FIG. 6 is a schematic structural diagram of an embodiment of a basestation according to the embodiments of the present invention;

FIG. 7 is a schematic structural diagram of a third embodiment of acommunications device in a high-frequency system according to theembodiments of the present invention;

FIG. 8 is a schematic structural diagram of an embodiment of userequipment according to the embodiments of the present invention;

FIG. 9 is a schematic flowchart of a first embodiment of a scanningmethod in a high-frequency system according to the embodiments of thepresent invention;

FIG. 10 is a schematic flowchart of a second embodiment of a scanningmethod in a high-frequency system according to the embodiments of thepresent invention; and

FIG. 11 is a schematic flowchart of a third embodiment of a scanningmethod in a high-frequency system according to the embodiments of thepresent invention.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The following clearly and completely describes the technical solutionsin the embodiments of the present invention with reference to theaccompanying drawings in the embodiments of the present invention.Apparently, the described embodiments are merely some but not all of theembodiments of the present invention. All other embodiments obtained bya person of ordinary skill in the art based on the embodiments of thepresent invention without creative efforts shall fall within theprotection scope of the present invention.

Refer to FIG. 1, which is a schematic structural diagram of a firstembodiment of a communications device in a high-frequency systemaccording to the embodiments of the present invention. Thecommunications device described in this embodiment includes: a scanmodule 10, configured to use a single beam for each space S region in ato-be-scanned sector of a cell to poll or cover all time T regions inthe S region in a time-division manner, and send a synchronizationsequence to user equipment in the T region by using a preset framestructure, where the frame structure is carried in a beam signal. Thecommunication device also includes a determining module 20, configuredto receive a sequence that is fed back by the user equipment, determinea location of the user equipment according to the sequence, anddetermine, according to the location of the user equipment, a servingbeam for a base station to communicate with the user equipment, toconfirm that scanning for the user equipment is completed.

In some feasible implementation manners, the communications devicedescribed in this embodiment may be specifically a base station, or adevice applied to a base station. In this embodiment of the presentinvention, a base station is used as an example for specificdescription.

In some feasible implementation manners, to implement full coverage(that is, signal scanning) of a base station signal in a cell, a basestation first needs to implement signal coverage in each sector of thecell, and further implements full coverage of the base station signal inthe cell by covering all sectors. Therefore, in this embodiment of thepresent invention, an implementation manner in which a base stationcovers a sector of a cell is first described specifically. When the basestation implements coverage in all sectors of the cell, full coverage inthe cell can be implemented.

In specific implementation, the base station may divide a sector of thecell into multiple space regions (S regions for short). Specifically,the cell may be any one of multiple cells that are covered by the basestation, and the cell may include multiple sectors. Coverage in any onesector is used as an example for specific description in this embodimentof the present invention. In this embodiment of the present invention, adivision action of dividing a sector of the cell into multiple S regionsmay be executed by the base station or be executed by another device.That is, the another device may be used to divide the cell into themultiple S regions and then send a division result to the base station,and the base station is used to implement signal coverage in the Sregions. In addition, a division action of dividing an S region intomultiple T regions described in this embodiment of the present inventionmay also be executed by the base station or be executed by anotherdevice, and after performing the division, the another device sends adivision result to the base station, and the base station implementscoverage in the T regions in the S region. No limitation is imposedherein. In the embodiments of the present invention, a base stationdivides a sector of a cell into multiple S regions, and then divideseach S region into multiple T regions, and a scanning method and anapparatus described in the embodiments of the present invention aredescribed specifically on this basis. Details are not described again inthe following embodiments.

In some feasible implementation manners, the base station may divide,according to a preset S region division rule, the to-be-scanned sector(that is, any one sector of the cell) in the cell into the multiple Sregions (in this embodiment of the present invention, M is used torepresent a quantity of S regions resulting from division of theto-be-scanned sector, M is a positive integer, and a magnitude of M maybe defined according to an actual situation). Specifically, according tothe preset S region division rule, the base station may evenly dividethe to-be-scanned sector into M equal-sized S regions, or may divide theto-be-scanned sector into M unequal-sized S regions. After dividing theto-be-scanned sector into the M S regions, the base station may furtherdivide each of the S regions into multiple smaller regions. That is, thebase station may divide, according to a preset time region (T region forshort) division rule, each S region into multiple T regions (in thisembodiment of the present invention, N is used to represent a quantityof T regions resulting from division of the S region, N is a positiveinteger, and a magnitude of N may be defined according to an actualsituation). For example, the base station may divide the to-be-scannedsector of the cell covered by the base station into 16 S regions, andthe 16 S regions may be arranged according to a scan direction of a beamemitted by the base station, that is, the 16 S regions may be arrangedinto a 4×4 region according to a horizontal scan direction and avertical scan direction of the beam. After dividing the sector into the16 S regions, the base station may further divide each S region into 16T regions, and may further arrange the 16 T regions according to apreset T region division rule. The base station may scan each T regionto implement signal coverage in an S region by means of signal coveragein all T regions, implement signal coverage in an entire sector by meansof signal coverage in all S regions, and implement signal coverage inthe entire cell by means of signal coverage in all sectors.

In some feasible implementation manners, after dividing theto-be-scanned sector into multiple S regions and dividing each S regioninto multiple T regions, the base station may poll or cover all the Tregions. Specifically, the scan module 10 of the base station may emitmultiple beams (for example, M1 beams, where M1 is a positive integer),and each beam may correspondingly cover one S region. In each S region,the scan module 10 may use a single beam to poll or cover all T regionsin the S region in a time-division manner. That is, all T regions in asame S region may receive a same beam emitted by the base station. Forexample, the scan module 10 may emit 16 high-frequency narrow beams,each beam correspondingly covers one S region, and in each S region,each beam polls and covers all T regions in a time-division manner. Thatis, a beam that covers an S region (for example, an Sn region) may pointto different T regions in the Sn region at different time points. Forexample, the beam may point to a Tn region in the Sn region at a Tn timepoint to scan the Tn region.

In some feasible implementation manners, when scanning T regions in an Sregion by using a beam emitted by the scan module 10, the scan module 10may also add, to a beam signal, a synchronization sequence that is to besent to user equipment, and sends the synchronization sequence to theuser equipment. Specifically, in this embodiment of the presentinvention, a frame structure may be predefined. As shown in FIG. 2, inthe foregoing frame structure, each radio frame may include K1equal-sized radio subframes, each radio subframe may include K2equal-sized timeslots, and each timeslot may include K3 OFDM symbols,where K1, K2, and K3 are positive integers, and magnitudes of K1, K2,and K3 may be defined according to an actual situation. Specifically,the base station may insert multiple OFDM symbols into one downlinktimeslot in one radio subframe in the frame structure, for sending thesynchronization sequence to the user equipment. A quantity of insertedOFDM symbols is equal to the quantity of T regions. In specificimplementation, an OFDM symbol includes multiple subcarriers in afrequency domain, and the base station may modulate a correspondingsequence symbol onto some specific subcarriers in the OFDM symbol, so asto insert the synchronization sequence into the OFDM symbol, and sendthe synchronization sequence to user equipment in a T region by usingthe OFDM symbol.

In some feasible implementation manners, the scan module 10 polls andcovers all T regions in each S region in a time-division manner andsends the synchronization sequence to user equipment in each of the Tregions by using the frame structure. After receiving the beam signalsent by the base station, the user equipment may obtain thesynchronization sequence from the beam signal and further feed back acorresponding sequence according to the obtained synchronizationsequence. After receiving the sequence sent by the user equipment, thedetermining module 20 of the base station may determine the location ofthe user equipment according to the sequence, and determines, accordingto the location of the user equipment, the serving beam for the basestation to communicate with the user equipment, to confirm that scanning(that is, signal coverage) for the user equipment is completed.

In this embodiment of the present invention, a base station may divide ato-be-scanned sector into multiple S regions and divides each S regioninto multiple T regions; a scan module may poll all the T regions ineach S region in a time-division manner, and further send asynchronization sequence to user equipment in a T region by using apreset frame structure; a determining module may determine a location ofthe user equipment according to a sequence that is fed back by the userequipment, and determine, according to the location of the userequipment, a serving beam for the base station to communicate with theuser equipment, so as to complete access to the user equipment. In thisembodiment of the present invention, when multiple beams are used, asingle beam may be used to poll all T regions in a time-division manner,which effectively improves a cell coverage rate under a beam freedomrestricted condition, improves user experience in using high-frequencynarrow beams to implement cell-wide coverage, and reduces costs forcell-wide coverage.

Refer to FIG. 3, which is a schematic structural diagram of a secondembodiment of a communications device in a high-frequency systemaccording to the embodiments of the present invention. Thecommunications device described in this embodiment includes: a divisionmodule 30, configured to divide a to-be-scanned sector of a cell intomultiple S regions according to a predefined S region division rule, anddivide each of the S regions into multiple T regions according to apreset T region division rule; a scan module 40, configured to use asingle beam for each space S region in the to-be-scanned sector of thecell to poll or cover all time T regions in the S region in atime-division manner, and send a synchronization sequence to userequipment in the T region by using a preset frame structure, where theframe structure is carried in a beam signal; and a determining module20, configured to receive a sequence that is fed back by the userequipment, determine a location of the user equipment according to thesequence, and determine, according to the location of the userequipment, a serving beam for a base station to communicate with theuser equipment, to confirm that scanning for the user equipment iscompleted.

In some feasible implementation manners, the division module 30 isspecifically configured to: determine, according to a quantity of beamsemitted by the base station, a quantity M of S regions resulting fromdivision of the to-be-scanned sector, where each of the S regions iscorresponding to one beam, and M is equal to the quantity of beams; anddivide, according to the S region division rule, the to-be-scannedsector into M equal-sized S regions, or M S regions whose sizes arecorresponding to widths of the beams.

In some feasible implementation manners, the division module 30 isspecifically configured to: determine, according to a beam width of abeam emitted by the base station and a size of the S region, a quantityN of T regions resulting from division of the S region; and divide eachof the S regions into N T regions in a same division order or adifferent division order according to the T region division rule.

In some feasible implementation manners, the scan module 40 isspecifically configured to: insert M OFDM symbols into one downlinktimeslot in one radio subframe in the frame structure, insert thesynchronization sequence into the OFDM symbols, and send thesynchronization sequence to the user equipment in the T region by usingthe OFDM.

In some feasible implementation manners, the communications devicedescribed in this embodiment of the present invention may use thedivision module 30 to perform region division on a cell. For a specificimplementation process in which the division module 30 performs regiondivision on a cell, refer to the specific implementation mannerdescribed in the first embodiment of the communications device in ahigh-frequency system according to the embodiments of the presentinvention, in which a base station performs region division on a cell.Details are not described herein again.

Further, when the division module 10 performs region division on thecell, the S region division rule and the T region division rule arefurther defined. Specifically, the S region division rule may include:evenly dividing the to-be-scanned sector of the cell to divide theto-be-scanned sector into multiple equal-sized S regions; or dividingthe to-be-scanned sector of the cell according to beam widths of beamsemitted by the base station, to divide the to-be-scanned sector intomultiple S regions whose sizes are corresponding to the beam widths. Inspecific implementation, when the division module 30 divides theto-be-scanned sector of the cell, the beam widths of the beams emittedby the scan module 40 may not be considered, and the to-be-scannedsector is directly divided into multiple equal-sized S regions. If thebeam widths of the beams emitted by the scan module 40 are considered,the division module 30 may divide the to-be-scanned sector of the cellaccording to the beam widths of the beams emitted by the scan module 40.Specifically, when a same beam width is used for the beams emitted bythe scan module 40, when dividing the to-be-scanned sector, the divisionmodule 30 may evenly divide the to-be-scanned sector, that is, maydivide a to-be-scanned region (that is, the to-be-scanned sector) intoequal-sized regions. In this case, a division result of theto-be-scanned sector is the same as a division result of theto-be-scanned sector when the beam widths are not considered. As shownin FIG. 4, when a same beam width is used for the beams emitted by thescan module 40, the division module 30 may divide the to-be-scannedsector into multiple equal-sized S regions (for example, S1-S16, 16equal-sized regions). In addition, when different beam widths are usedfor the beams emitted by the scan module 40, when dividing theto-be-scanned sector, the division module 30 may unevenly divide theto-be-scanned sector, that is, may divide, according to a specific beamwidth of each beam, a to-be-scanned region (that is, the to-be-scannedsector) into multiple unequal-sized regions corresponding to the beamwidths. For example, when different beam widths are used for the beamsemitted by the scan module 40, the division module 30 may divide theto-be-scanned sector into 16 S regions, where sizes of the S regions areunequal, and a size of each S region is specifically corresponding tothe beam width of each beam. In specific implementation, the divisionmodule 30 may divide the to-be-scanned sector of the cell into multiple(for example, M) S regions according to the preset S region divisionrule. Specifically, the division module 30 may first determine aquantity M1 of beams that are emitted by the scan module 40, anddetermines, according to M1, the quantity M of S regions resulting fromdivision of the to-be-scanned sector. Among the beams emitted by thebase station, one beam may cover one S region. Therefore, the divisionmodule 30 may determine, according to the quantity of beams emitted bythe scan module 40, the quantity of S regions resulting from division ofthe to-be-scanned sector into S regions, that is, M is equal to M1.After M is determined, the division module 30 may divide, according tothe S region division rule, the to-be-scanned sector into M equal-sizedS regions, or M S regions whose sizes are corresponding to the beamwidths. In addition, in this embodiment of the present invention, thesizes of the S regions may be determined jointly by a quantity ofantenna array elements and a cell range. More antenna array elementsindicate more beams that can be formed, that is, more beams that can beemitted by the base station; and the quantity of S regions iscorresponding to the quantity of beams, that is, M is equal to M1.Therefore, when the quantity of antenna array elements is definite, alarger cell range indicates a corresponding larger size of each Sregion; and when the cell range is definite, more antenna array elementsindicate a corresponding smaller size of each S region.

In some feasible implementation manners, the division module 30 furtherdefines the T region division rule. Specifically, the T region divisionrule may include: dividing all the S regions in a same division order todivide each S region into multiple T regions; or dividing different Sregions in different division orders to divide each S region intomultiple T regions. In specific implementation, when dividing an Sregion (for example an Sn region), the division module 30 may firstdetermine, according to a beam width of a beam emitted by the scanmodule 40 and a size of the Sn region, the quantity N of T regionsresulting from division of the Sn region. Specifically, according to abeam width of a beam emitted by the base station a region size for eachscan by the beam may be determined, and with reference to the size ofthe Sn region, how many scans the beam needs to perform to poll theentire S region may be determined. Therefore, the division module 30 maydetermine, according to the beam width of the beam emitted by the scanmodule 40 and the size of the Sn region, the quantity N of regions (thatis, the quantity of T regions) resulting from division of the S region.After determining the N T regions resulting from division of the Snregion, the division module 30 may divide the Sn region into N T regionsin a division order (a same division order or a different divisionorder) specified in the T region division rule. As shown in FIG. 4, thedivision module 30 may divide an S7 region into 16 even T regionsaccording to a beam width and a size of the S7 region. Specifically, thedivision module 30 may divide the S7 region into 16 T regions in adivision order specified in the preset T region division rule (assumablya division rule 1). In addition, the division module 30 may furtherdivide another S region into 16 T regions according to the division rule1, and each division order of T regions is the same as the divisionorder of T regions in the S7 region. In specific implementation, asshown in FIG. 5, the division module 30 may alternatively divide the S7region into 16 even T regions according to a beam width and a size ofthe S7 region. Specifically, the division module 30 may divide the S7region into 16 T regions in a division order specified in the preset Tregion division rule (assumably a division rule 2), and divide another Sregion into 16 regions according to the division rule 2. In addition, nodivision order of T regions is the same as the division rule T regionsin the S7 region, for example, an S6 region and the S7 region.

In some feasible implementation manners, after the division module 30divides the to-be-scanned sector into multiple S regions and divideseach S region into multiple T regions, the scan module 40 may poll orcover all the T regions. In specific implementation, the scan module 40described in this embodiment may implement a function of the scan module10 described in the first embodiment of the communications device in ahigh-frequency system according to the embodiments of the presentinvention. For a specific implementation process in which the scanmodule 40 polls and covers all T regions, refer to the specificimplementation manner of the scan module 10 in the first embodiment ofthe scanning method in a high-frequency system according to theembodiments of the present invention. Details are not described hereinagain.

Further, when scanning T regions in an S region by using a beam emittedby the scan module 40, the scan module 40 may also add, to a beamsignal, a synchronization sequence that is to be sent to user equipment,and sends the synchronization sequence to the user equipment.Specifically, in this embodiment of the present invention, a framestructure may be predefined. As shown in FIG. 2, in the foregoing framestructure, each radio frame may include K1 equal-sized radio subframes,each radio subframe may include K2 equal-sized timeslots, and eachtimeslot may include K3 OFDM symbols, where K1, K2, and K3 are positiveintegers. Specifically, the base station may insert multiple OFDMsymbols into one downlink timeslot in one radio subframe in the framestructure, for sending the synchronization sequence to the userequipment. A quantity of inserted OFDM symbols is equal to the quantityof T regions. In specific implementation, an OFDM symbol includesmultiple subcarriers in a frequency domain, and the base station maymodulate a corresponding sequence symbol onto some specific subcarriersin the OFDM symbol, so as to insert the synchronization sequence intothe OFDM symbol, and send the synchronization sequence to user equipmentin a T region by using the OFDM symbol.

Further, in this embodiment of the present invention, thesynchronization sequence that is sent by the scan module 40 to the userequipment may include an ID of the beam that is emitted by the basestation to cover the T region. The T region (assumably T1) covered bythe beam is a T region in which the user equipment is located.Specifically, the ID of the beam may include a cell sequence C_ID, asector sequence SEC_ID, a space sequence S_ID, and a time sequence T_ID.The T_ID is an ID corresponding to T1, the S_ID is an ID of an S region(assumably S6) in which T1 is located, the SEC_ID is an ID of a sector(assumably a sector 1) in which S6 is located, and the C_ID is an ID ofa cell in which the sector 1 is located.

In some feasible implementation manners, after the scan module 40 pollsand covers all T regions in each S region in a time-division manner andsends the synchronization sequence to user equipment in each of the Tregions by using the frame structure, the user equipment may emit anarrow beam to perform scanning and receive the beam signal transmittedby the base station. After receiving the beam signal sent by the basestation, the user equipment may obtain the synchronization sequence fromthe beam signal and further feed back a corresponding sequence accordingto the obtained synchronization sequence. After receiving the sequencesent by the user equipment, the determining module 20 of the basestation may determine a location of the user equipment, to confirm thatscanning for the user equipment is completed.

In this embodiment of the present invention, a base station may use adivision module to evenly (or unevenly) divide a to-be-scanned sectorinto multiple S regions according to a predefined S region division ruleand divide each S region into multiple T regions according to apredefined T region division rule; and further use a scan module 40 topoll all T regions in each S region in a time-division manner. Inaddition, the base station may send a synchronization sequence to userequipment in the T region by using a preset frame structure; and finallydetermine, by using a determining module, a location of the userequipment according to a sequence that is fed back by the userequipment. In this embodiment of the present invention, when multiplebeams are used, a single beam may be used to poll all T regions in atime-division manner, which effectively improves a cell coverage rateunder a beam freedom restricted condition, improves user experience inusing high-frequency narrow beams to implement cell-wide coverage, andreduces costs for cell-wide coverage.

Refer to FIG. 6, which is a schematic structural diagram of anembodiment of a base station according to the embodiments of the presentinvention. The base station described in this embodiment includes: aprocessor 100, configured to use a single beam for each space S regionin a to-be-scanned sector of a cell to poll or cover all time T regionsin the S region in a time-division manner; a transmitter 200, configuredto send, by using a preset frame structure, a synchronization sequenceto user equipment in the T region that is obtained by means ofprocessing by the processor, where the frame structure is carried in abeam signal; and a receiver 300, configured to receive a sequence thatis fed back by the user equipment.

The processor 100 is further configured to determine a location of theuser equipment according to the sequence, and determine, according tothe location of the user equipment, a serving beam for the base stationto communicate with the user equipment, to confirm that scanning for theuser equipment is completed.

In some feasible implementation manners, the processor 100 is furtherspecifically configured to: divide the to-be-scanned sector of the cellinto multiple S regions according to a predefined S region divisionrule, and divide each of the S regions into multiple T regions accordingto a preset T region division rule.

In some feasible implementation manners, the processor 100 isspecifically configured to: determine, according to a quantity of beamsemitted by the base station, a quantity M of S regions resulting fromdivision of the to-be-scanned sector, where each of the S regions iscorresponding to one beam, and M is equal to the quantity of beams; anddivide, according to the S region division rule, the to-be-scannedsector into M equal-sized S regions, or M S regions whose sizes arecorresponding to widths of the beams.

In some feasible implementation manners, the processor 100 is furtherspecifically configured to: determine, according to a beam width of abeam emitted by the base station and a size of the S region, a quantityN of T regions resulting from division of the S region; and divide eachof the S regions into N T regions in a same division order or adifferent division order according to the T region division rule.

In some feasible implementation manners, the transmitter 200 isspecifically configured to: insert M OFDM symbols into one downlinktimeslot in one radio subframe in the frame structure, insert thesynchronization sequence into the OFDM symbols, and send thesynchronization sequence to the user equipment in the T region by usingthe OFDM.

In some feasible implementation manners, for a specific implementationprocess of the base station described in this embodiment of the presentinvention, refer to the implementation manners that are described in thefirst embodiment and the second embodiment of the communications devicein a high-frequency system according to the embodiments of the presentinvention. That is, the base station described in this embodiment of thepresent invention may be the communications device in a high-frequencysystem according to the embodiments of the present invention, describedin the first embodiment or the second embodiment. The processor 100, thetransmitter 200, and the receiver 300 that are included in the basestation may be specifically applied to the division module, the scanmodule, and the determining module that are in the communications devicein a high-frequency system according to the embodiments of the presentinvention, described in the first embodiment or the second embodiment.For a specific implementation process, refer to the specificimplementation process of the communications device in a high-frequencysystem according to the embodiments of the present invention, describedin the first embodiment or the second embodiment. Details are notdescribed herein again.

Refer to FIG. 7, which is a schematic structural diagram of a thirdembodiment of a communications device in a high-frequency systemaccording to the embodiments of the present invention. Thecommunications device described in this embodiment includes: a receivingmodule 50, configured to emit a beam to perform beam signal scanning andreceive beam signals transmitted by a base station; a processing module60, configured to obtain synchronization sequences from the beam signalsreceived by the receiving module, and correlate all the synchronizationsequences; a selection module 70, configured to select a synchronizationsequence whose correlation peak value is the largest among correlationpeak values that are of all the synchronization sequences and that areobtained by means of processing by the processing module, and set a beamcorresponding to the synchronization sequence as a serving beam; and afeedback module 80, configured to insert, into a specified orthogonalfrequency division multiplexing OFDM symbol, a sequence corresponding toan ID of the serving beam that is selected by the selection module, andfeed back the sequence corresponding to the ID of the serving beam tothe base station.

In some feasible implementation manners, the processing module 60 isspecifically configured to: obtain an ID of the beam corresponding tothe synchronization sequence from OFDM symbols in the beam signal, andsequentially correlate a C_ID, a SEC_ID, an S_ID, and a T_ID in the IDof the beam.

In some feasible implementation manners, the feedback module 80 isspecifically configured to: select an OFDM symbol corresponding to aT_ID of the serving beam from OFDM symbols in an uplink timeslot; andinsert sequences corresponding to a C_ID, a SEC_ID, and an S_ID of theserving beam into the selected OFDM symbol, and feed back the sequencecorresponding to the ID of the serving beam to the base station by usingthe uplink timeslot.

In some feasible implementation manners, the feedback module 80 isspecifically configured to: predefine an OFDM symbol in the uplinktimeslot; and insert sequences corresponding to a C_ID, a SEC_ID, anS_ID, and a T_ID of the serving beam into the predefined OFDM symbol,and feed back the sequence corresponding to the ID of the serving beamto the base station by using the uplink timeslot.

In some feasible implementation manners, the communications device in ahigh-frequency system described in this embodiment may be specificallyuser equipment, and the user equipment is any user equipment in a cellcovered by the base station. In the following embodiment, the userequipment is used as an example to specifically describe thecommunications device in a high-frequency system according to theembodiments of the present invention.

In some feasible implementation manners, the receiving module 50 of theuser equipment may emit a narrow beam to perform scanning, to align witha beam emitted by the base station. The user equipment does not know aspecific location of the base station, and therefore, the user equipmentneeds to perform rotational scanning in an entire space range by usingthe beam emitted by the user equipment. A size of the entire range thatthe user equipment needs to scan may be predefined. When the beamemitted by the user equipment (also referred to as a receive beam) isperfectly aligned with the beam emitted by the base station (alsoreferred to as a transmit beam), signal power received by the userequipment is the highest, which means that when the receive beam of theuser equipment is not aligned with the transmit beam of the basestation, signal power received by the user equipment is lower, whichdoes not help signal demodulation. When the receive beam of the userequipment is perfectly aligned with the transmit beam of the basestation, the signal power received by the user equipment is the highest,and the receiving module 50 may obtain information such as thesynchronization sequence from the transmit beam of the base station. Inspecific implementation, a rotational scan cycle of the beam emitted bythe receiving module 50 of the user equipment needs to be greater thanor equal to a scan cycle of the base station, to better find a beam thatis emitted by the base station and that matches the beam. When the beamof the user equipment performs scanning, a beam direction may be changedonce at the end of each beam switching cycle until all-around beamscanning is completed. Specifically, the switching cycle may be a timethat a beam emitted by the user equipment stays in one scan direction.

In some feasible implementation manners, after the receiving module 50obtains the synchronization sequences from the transmit beams of thebase station, the processing module 60 may correlate the synchronizationsequences that are received by the receiving module 50. Specifically, inthis embodiment of the present invention, each beam signal sent by thebase station and received by the receiving module 50 carries a presetframe structure. In the frame structure, each radio frame includes K1equal-sized radio subframes, each radio subframe includes K2 equal-sizedtimeslots, and each timeslot includes K3 OFDM symbols, as shown in FIG.2, where K1, K2, and K3 are positive integers, and magnitudes of K1, K2,and K3 may be defined according to an actual situation, which are notlimited in this embodiment of the present invention. The synchronizationsequence sent by the base station is carried in OFDM symbols in theframe structure. The processing module 60 of the user equipment maylearn, from the beam signal transmitted by the base station and receivedby the receiving module 50, a frame structure that is used by the basestation to send the synchronization sequence, and obtain thesynchronization sequence from the OFDM symbols in the frame structure,and may further obtain the ID of the beam from the OFDM symbols, wherethe synchronization sequence is corresponding to the ID of the beam inthe OFDM symbols. Specifically, the ID of the waveform described in thisembodiment of the present invention may include a cell sequence C_ID, asector sequence SEC_ID, a space sequence S_ID, a time sequence T_ID, andso on. The T_ID is an ID corresponding to a T region (assumably T1) inwhich the user equipment is located when the base station sends thesynchronization sequence to the user equipment, the S_ID is an ID of anS region (assumably S6) in which T1 is located, the SEC_ID is an ID of asector (assumably a sector 1) in which S6 is located, and the C_ID is anID of a cell in which the sector 1 is located.

In some feasible implementation manners, because a cell in which theuser equipment is located may be covered by multiple base stations, theuser equipment may receive multiple beam signals from multiple cells.Therefore, the user equipment needs to select, from the beam signalstransmitted by the base stations, an optimal beam to be a serving beamfor the user equipment. In this embodiment of the present invention, theoptimal beam is a beam that matches the beam emitted by the userequipment, and the matching beam may be specifically a pair of beamswhose correlation peak values are the largest. In specificimplementation, after obtaining the synchronization sequences from thebeam signals transmitted by the base station, the processing module 60may correlate all synchronization sequences that are transmitted by allthe base stations, to obtain a beam whose correlation peak valuerelative to the beam emitted by the user equipment is the largest.Specifically, the processing module 60 may obtain, from an OFDM symbolof each beam signal, an ID of a beam corresponding to eachsynchronization sequence, and sequentially correlate a C_ID, a SEC_ID,an S_ID, and a T_ID that are in the ID of the beam. The selection module70 may select, according to a correlation result that is obtained bymeans of processing by the processing module 60, a synchronizationsequence whose correlation peak value is the largest, and set a beamcorresponding to the synchronization sequence as the serving beam forthe user equipment. An ID of the beam is an optimal ID. Specifically,the beam direction of the beam emitted by the user equipment changesonce at the end of each switching cycle, and therefore, after obtaininga serving beam in one switching cycle, when the beam of the userequipment enters a next switching cycle to perform scanning, the userequipment may obtain a serving beam for the next switching cycle. Byanalogy, when a scan cycle of the user equipment ends, the userequipment may obtain multiple serving beams. The selection module 70 maysort optimal IDs corresponding to all the serving beams, and select oneoptimal ID group to be an ID of a final serving beam for the userequipment.

In some feasible implementation manners, after selecting the servingbeam by using the selection module 70, the user equipment may feed back,to the base station by using the feedback module 80, the ID of theserving beam including the C_DI, SEC_ID, S_ID, and T_ID, to finallycomplete signal scanning in the high-frequency system. In specificimplementation, the feedback module 80 of the user equipment may select,from OFDM symbols in the uplink timeslot, the OFDM symbol correspondingto the T_ID of the serving beam, insert the sequences corresponding tothe C_DI, SEC_ID, and S_ID of the serving beam into the OFDM symbol, andfeed back the sequence corresponding to the ID of the serving beam tothe base station by using the uplink timeslot. That is, an order ofuplink feedback OFDM symbols in the uplink timeslot stays the same as anorder of downlink synchronization OFDM symbols in a downlink timeslot.In this case, the user equipment does not need to feed back the T_ID ofthe serving beam, and when receiving the ID of the serving beam that isfed back by the user equipment, the base station may determine the T_IDof the serving beam according to a location of an OFDM that is used tofeed back the beam ID. In the foregoing feedback manner, the feedbackmodule 80 needs to select, from the OFDM symbols in the uplink timeslot,the OFDM symbol corresponding to the T_ID of the serving beam to be theOFDM that is used to feed back the beam ID, and does not need to feedback a sequence corresponding to the T_ID of the serving beam, which canreduce feedback sequences. For example, if an optimal ID correspondingto the serving beam that is selected by the selection module 70 isC_ID=1, SEC_ID=3, S_ID=5, and T_ID=8, the feedback module 80 may insertsequences respectively corresponding to the C_ID=1, SEC_ID=3, and S_ID=5into a T8 OFDM symbol in the uplink feedback timeslot, and does not needto feed back a sequence corresponding to the T_ID to the base station.In specific implementation, the sequences, described in this embodimentof the present invention, which are corresponding to the C_ID, SEC_ID,and S_ID and which are fed back by the feedback module 80 are allorthogonal sequences, and the orthogonal sequences may be preset.

In some feasible implementation manners, the user equipment may furtherdefine an OFDM symbol in an uplink timeslot in advance. This OFDM symbolis used to feed back the ID of the serving beam to the base station,that is, the user equipment does not need to make a selection from allthe OFDMs in the uplink timeslot. After the selection module 70 of theuser equipment selects the serving beam, the feedback module 80 mayinsert the sequences corresponding to the C_ID, SEC_ID, S_ID, and T_IDof the serving beam into the predefined OFDM symbol, and feed back thesequence corresponding to the ID of the serving beam to the base stationby using the predefined OFDM symbol in the uplink timeslot. For example,if an optimal ID corresponding to the serving beam that is selected bythe selection module 70 is C_ID=1, SEC_ID=3, S_ID=5, and T_ID=8,sequences respectively corresponding to the C_ID=1, SEC_ID=3, S_ID=5,and T_ID=8 may be inserted into the predefined OFDM symbol (for example,a second OFDM symbol) in the uplink feedback timeslot. That is, the userequipment does not need to select an OFDM symbol from all the OFDMsymbols to be an OFDM symbol that is used to feed back the ID of theserving beam, but needs to feed back the sequence corresponding to theT_ID to the base station. In specific implementation, the sequences,described in this embodiment of the present invention, which arecorresponding to the C_ID, SEC_ID, S_ID, and T_ID and which are fed backby the user equipment are all orthogonal sequences, and the orthogonalsequences may be preset.

In this embodiment of the present invention, user equipment may obtainsynchronization sequences from beam signals transmitted by a basestation, and select a beam corresponding to an optimal ID to be aserving beam by means of sequence correlation, and may further feed backthe ID of the serving beam to the base station, to completesynchronization scanning in a high-frequency system. When feeding backthe ID of the serving beam to the base station, the user equipment mayperform the feedback in an OFDM symbol that is determined according tothe ID of the serving beam, or may perform the feedback in a predefinedOFDM symbol. This diversifies feedback manners, and improves userexperience in synchronization scanning.

Refer to FIG. 8, which is a schematic structural diagram of anembodiment of user equipment according to the embodiments of the presentinvention. The user equipment described in this embodiment includes: areceiver 500, configured to emit a beam to perform beam signal scanningand receive beam signals transmitted by a base station; and a processor600, configured to obtain synchronization sequences from the beamsignals received by the receiver, and correlate all the synchronizationsequences, where the processor 600 is configured to select asynchronization sequence whose correlation peak value is the largestamong correlation peak values of all the synchronization sequences, andset a beam corresponding to the synchronization sequence as a servingbeam; and the processor 600 is configured to insert a sequencecorresponding to an ID of the serving beam into a specified orthogonalfrequency division multiplexing OFDM symbol; and a transmitter 700,configured to feed back the sequence corresponding to the ID of theserving beam to the base station.

In some feasible implementation manners, the processor 600 isspecifically configured to: select an OFDM symbol corresponding to aT_ID of the serving beam from OFDM symbols in an uplink timeslot; andinsert sequences corresponding to a C_ID, a SEC_ID, and an S_ID of theserving beam into the selected OFDM symbol; and the transmitter 700 isspecifically configured to: feed back the sequence corresponding to theID of the serving beam to the base station by using the uplink timeslot.

In some feasible implementation manners, the processor 600 isspecifically configured to: predefine an OFDM symbol in the uplinktimeslot; and insert sequences corresponding to a C_ID, a SEC_ID, anS_ID and a T_ID of the serving beam into the predefined OFDM symbol; andthe transmitter 700 is specifically configured to: feed back thesequence corresponding to the ID of the serving beam to the base stationby using the uplink timeslot.

In some feasible implementation manners, for a specific implementationprocess of the user described in this embodiment of the presentinvention, refer to the implementation manner described in the thirdembodiment of the communications device in a high-frequency systemaccording to the embodiments of the present invention. That is, the userequipment described in this embodiment of the present invention may bethe communications device in a high-frequency system according to theembodiments of the present invention, described in the third embodiment.The receiver 500, the processor 600, and the transmitter 700 that areincluded in the base station may be specifically applied to thereceiving module, the processing module, the selection module and thefeedback module that are in the communications device in ahigh-frequency system according to the embodiments of the presentinvention, described in the third embodiment. For a specificimplementation process, refer to the specific implementation process ofthe communications device in a high-frequency system according to theembodiments of the present invention, described in the third embodiment.Details are not described herein again.

Refer to FIG. 9, which is a schematic flowchart of a first embodiment ofa scanning method in a high-frequency system according to theembodiments of the present invention. The scanning method described inthis embodiment includes the following steps.

S101. A base station uses a single beam for each space S region in ato-be-scanned sector of a cell to poll or cover all time T regions inthe S region in a time-division manner, and sends a synchronizationsequence to user equipment in the T region by using a preset framestructure, where the frame structure is carried in a beam signal.

S102. The base station receives a sequence that is fed back by the userequipment, determines a location of the user equipment according to thesequence, and determines, according to the location of the userequipment, a serving beam for the base station to communicate with theuser equipment, to confirm that scanning for the user equipment iscompleted.

In some feasible implementation manners, to implement full coverage of abase station signal in a cell, a base station first needs to implementsignal coverage (that is, scanning) in each sector of the cell, andfurther implement full coverage of the base station signal in the cellby covering all sectors. Therefore, in this embodiment of the presentinvention, an implementation manner in which a base station covers asector of a cell is first described specifically. When the base stationimplements coverage in all sectors of the cell, full coverage in thecell can be implemented.

In specific implementation, the base station may divide a sector of thecell into multiple space regions (S regions for short). Specifically,the cell may be any one of multiple cells that are covered by the basestation, and the cell may include multiple sectors. Coverage in any onesector is used as an example for specific description in this embodimentof the present invention. In this embodiment of the present invention, adivision action of dividing a sector of the cell into multiple S regionsmay be executed by the base station or be executed by another device.That is, the another device may be used to divide the cell into themultiple S regions and then send a division result to the base station,and the base station is used to implement signal coverage in the Sregions. In addition, a division action of dividing an S region intomultiple T regions described in this embodiment of the present inventionmay also be executed by the base station or be executed by anotherdevice, and after performing the division, the another device sends adivision result to the base station, and the base station implementscoverage in the T regions in the S region. No limitation is imposedherein. In the embodiments of the present invention, a base stationdivides a sector of a cell into multiple S regions, and then divideseach S region into multiple T regions, and a scanning method and anapparatus described in the embodiments of the present invention aredescribed specifically on this basis. Details are not described again inthe following embodiments.

In some feasible implementation manners, the base station may divide,according to a preset S region division rule, the to-be-scanned sector(that is, any one sector of the cell) in the cell into the multiple Sregions (in this embodiment of the present invention, M is used torepresent a quantity of S regions resulting from division of theto-be-scanned sector, M is a positive integer, and a magnitude of M maybe defined according to an actual situation). Specifically, according tothe preset S region division rule, the base station may evenly dividethe to-be-scanned sector into M equal-sized S regions, or may divide theto-be-scanned sector into M unequal-sized S regions. After dividing theto-be-scanned sector into the M S regions, the base station may furtherdivide each of the S regions into multiple smaller regions. That is, thebase station may divide, according to a preset time region (T region forshort) division rule, each S region into multiple T regions (in thisembodiment of the present invention, N is used to represent a quantityof T regions resulting from division of the S region, N is a positiveinteger, and a magnitude of N may be defined according to an actualsituation). For example, the base station may divide the to-be-scannedsector of the cell covered by the base station into 16 S regions, andthe 16 S regions may be arranged according to a scan direction of a beamemitted by the base station, that is, the 16 S regions may be arrangedinto a 4×4 region according to a horizontal scan direction and avertical scan direction of the beam. After dividing the sector into the16 S regions, the base station may further divide each S region into 16T regions, and may further arrange the 16 T regions according to apreset T region division rule. The base station may scan each T regionto implement signal coverage in an S region by means of signal coveragein all T regions, implement signal coverage in an entire sector by meansof signal coverage in all S regions, and implement signal coverage inthe entire cell by means of signal coverage in all sectors.

In some feasible implementation manners, after dividing theto-be-scanned sector into multiple S regions and dividing each S regioninto multiple T regions, the base station may poll or cover all the Tregions. Specifically, the base station may emit multiple beams (forexample, M1 beams, where M1 is a positive integer), and each beam maycorrespondingly cover one S region. In each S region, the base stationmay use a single beam to poll or cover all T regions in the S region ina time-division manner. That is, all T regions in a same S region mayreceive a same beam emitted by the base station. For example, the basestation may emit 16 high-frequency narrow beams, each beamcorrespondingly covers one S region, and in each S region, each beampolls and covers all T regions in a time-division manner. That is, abeam that covers an S region (for example, an Sn region) may point todifferent T regions in the Sn region at different time points. Forexample, the beam may point to a Tn region in the Sn region at a Tn timepoint to scan the Tn region.

In some feasible implementation manners, when scanning T regions in an Sregion by using a beam emitted by the base station, the base station mayalso add, to a beam signal, a synchronization sequence that is to besent to user equipment, and sends the synchronization sequence to theuser equipment. Specifically, in this embodiment of the presentinvention, a frame structure may be predefined. As shown in FIG. 2, inthe foregoing frame structure, each radio frame may include K1equal-sized radio subframes, each radio subframe may include K2equal-sized timeslots, and each timeslot may include K3 OFDM symbols,where K1, K2, and K3 are positive integers, and magnitudes of K1, K2,and K3 may be defined according to an actual situation. Specifically,the base station may insert multiple OFDM symbols into one downlinktimeslot in one radio subframe in the frame structure, for sending thesynchronization sequence to the user equipment. A quantity of insertedOFDM symbols is equal to the quantity of T regions. In specificimplementation, an OFDM symbol includes multiple subcarriers in afrequency domain, and the base station may modulate a correspondingsequence symbol onto some specific subcarriers in the OFDM symbol, so asto insert the synchronization sequence into the OFDM symbol, and sendthe synchronization sequence to user equipment in a T region by usingthe OFDM symbol.

In some feasible implementation manners, the base station polls andcovers all T regions in each S region in a time-division manner andsends the synchronization sequence to user equipment in each of the Tregions by using the frame structure. After receiving the beam signalsent by the base station, the user equipment may obtain thesynchronization sequence from the beam signal and further feed back acorresponding sequence according to the obtained synchronizationsequence. After receiving the sequence sent by the user equipment, thebase station may determine the location of the user equipment accordingto the sequence, and determines, according to the location of the userequipment, the serving beam for the base station to communicate with theuser equipment, to confirm that scanning (that is, signal coverage) forthe user equipment is completed.

In this embodiment of the present invention, a base station may divide ato-be-scanned sector into multiple S regions and divides each S regioninto multiple T regions and further poll all the T regions in each Sregion in a time-division manner. In addition, the base station may senda synchronization sequence to user equipment in a T region by using apreset frame structure, determine a location of the user equipmentaccording to a sequence that is fed back by the user equipment, anddetermine, according to the location of the user equipment, a servingbeam for the base station to communicate with the user equipment, so asto complete access to the user equipment. In this embodiment of thepresent invention, when multiple beams are used, a single beam may beused to poll all T regions in a time-division manner, which effectivelyimproves a cell coverage rate under a beam freedom restricted condition,improves user experience in using high-frequency narrow beams toimplement cell-wide coverage, and reduces costs for cell-wide coverage.

Refer to FIG. 10, which is a schematic flowchart of a second embodimentof a scanning method in a high-frequency system according to theembodiments of the present invention. The scanning method described inthis embodiment includes the following steps:

S201. A base station determines, according to a quantity of beamsemitted by the base station, a quantity M of S regions resulting fromdivision of a to-be-scanned sector.

S202. Divide, according to an S region division rule, the to-be-scannedsector into M equal-sized S regions, or M S regions whose sizes arecorresponding to widths of the beams.

In some feasible implementation manners, for a specific implementationprocess, described in this embodiment of the present, in which the basestation performs region division on a cell, refer to step S101 and S102in the first embodiment of the scanning method in a high-frequencysystem according to the embodiments of the present invention, anddetails are not described herein again.

Further, in this embodiment of the present invention, the S regiondivision rule and a T region division rule are further defined.Specifically, the S region division rule may include: evenly dividingthe to-be-scanned sector of the cell to divide the to-be-scanned sectorinto multiple equal-sized S regions; or dividing the to-be-scannedsector of the cell according to beam widths of beams emitted by the basestation, to divide the to-be-scanned sector into multiple S regionswhose sizes are corresponding to the beam widths. In specificimplementation, when the base station divides the to-be-scanned sectorof the cell, the beam widths of the beams emitted by the base stationmay not be considered, and the to-be-scanned sector is directly dividedinto multiple equal-sized S regions. If the beam widths of the beamsemitted by the base station are considered, the to-be-scanned sector ofthe cell may be divided according to the beam widths of the beamsemitted by the base station. Specifically, when a same beam width isused for the beams emitted by the base station, when dividing theto-be-scanned sector, the base station may evenly divide theto-be-scanned sector, that is, may divide a to-be-scanned region (thatis, the to-be-scanned sector) into equal-sized regions. In this case, adivision result of the to-be-scanned sector is the same as a divisionresult of the to-be-scanned sector when the beam widths are notconsidered. As shown in FIG. 4, when a same beam width is used for thebeams emitted by the base station, the to-be-scanned sector may bedivided into multiple equal-sized S regions (for example, S1-S16, 16equal-sized regions). In addition, when different beam widths are usedfor the beams emitted by the base station, when dividing theto-be-scanned sector, the base station may unevenly divide theto-be-scanned sector, that is, may divide, according to a specific beamwidth of each beam, a to-be-scanned region (that is, the to-be-scannedsector) into multiple unequal-sized regions corresponding to the beamwidths. For example, when different beam widths are used for the beamsemitted by the base station, the base station may divide theto-be-scanned sector into 16 S regions, where sizes of the S regions areunequal, and a size of each S region is specifically corresponding tothe beam width of each beam. In specific implementation, the basestation may divide the to-be-scanned sector of the cell into multiple(for example, M) S regions according to the preset S region divisionrule. Specifically, the base station may determine, according to a beamfreedom restricted condition, a quantity M1 of beams that are emitted bythe base station, and determine, according to M1, the quantity M of Sregions resulting from division of the to-be-scanned sector. Among thebeams emitted by the base station, one beam may cover one S region.Therefore, the base station may determine, according to the quantity ofbeams emitted by the base station, the quantity of S regions resultingfrom division of the to-be-scanned sector into S regions, that is, M isequal to M1. After M is determined, the base station may divide,according to the S region division rule, the to-be-scanned sector into Mequal-sized S regions, or M S regions whose sizes are corresponding tothe beam widths. In addition, in this embodiment of the presentinvention, the sizes of the S regions may be determined jointly by aquantity of antenna array elements and a cell range. More antenna arrayelements indicate more beams that can be formed, that is, more beamsthat can be emitted by the base station; and the quantity of S regionsis corresponding to the quantity of beams, that is, M is equal to M1.Therefore, when the quantity of antenna array elements is definite, alarger cell range indicates a corresponding larger size of each Sregion; and when the cell range is definite, more antenna array elementsindicate a corresponding smaller size of each S region.

S203. Determine, according to a beam width of a beam emitted by the basestation and a size of the S region, a quantity N of T regions resultingfrom division of the S region.

S204. Divide each of the S regions into N T regions in a same divisionorder or a different division order according to a T region divisionrule.

In some feasible implementation manners, in this embodiment of thepresent invention, the T region division rule is further defined.Specifically, the T region division rule may include: dividing all the Sregions in a same division order to divide each S region into multiple Tregions; or dividing different S regions in different division orders todivide each S region into multiple T regions. In specificimplementation, when dividing an S region (assumably an Sn region), thebase station may first determine, according to a beam width of a beamemitted by the base station and a size of the Sn region, the quantity Nof T regions resulting from division of the Sn region. Specifically,according to a beam width of a beam emitted by the base station, aregion size for each scan by the beam may be decided, and with referenceto the size of the Sn region, how many scans the beam needs to performto poll the entire S region may be determined. Therefore, the basestation may determine, according to the beam width of the beam emittedby the base station and the size of the Sn region, the quantity N ofregions (that is, the quantity of T regions) resulting from division ofthe S region. After determining the N T regions resulting from divisionof the Sn region, the base station may divide the Sn region into N Tregions in a division order (a same division order or a differentdivision order) specified in the T region division rule. As shown inFIG. 4, the base station may divide an S7 region into 16 even T regionsaccording to a beam width and a size of the S7 region. Specifically, theS7 region may be divided into 16 T regions in a division order specifiedin the preset T region division rule (assumably a division rule 1). Inaddition, the base station may further divide another S region into 16 Tregions according to the division rule 1, and each division order of Tregions is the same as the division order of T regions in the S7 region.In specific implementation, as shown in FIG. 5, the base station mayalternatively divide the S7 region into 16 even T regions according to abeam width and a size of the S7 region. Specifically, the base stationmay divide the S7 region into 16 T regions in a division order specifiedin the preset T region division rule (assumably a division rule 2), anddivide another S region into 16 regions according to the division rule2. In addition, no division order of T regions is the same as thedivision rule of T regions in the S7 region, for example, an S6 regionand the S7 region.

S205. The base station uses a single beam to poll or cover all T regionsin an S region in a time-division manner and sends a synchronizationsequence to user equipment in the T region by using a preset framestructure.

S206. The base station receives a sequence that is fed back by the userequipment, determines a location of the user equipment according to thesequence, and determines, according to the location of the userequipment, a serving beam for the base station to communicate with theuser equipment, to confirm that scanning for the user equipment iscompleted.

In some feasible implementation manners, after dividing theto-be-scanned sector into multiple S regions and dividing each S regioninto multiple T regions, the base station may poll or cover all the Tregions. In specific implementation, for a specific implementationprocess in which the base station polls and covers all the T regions,refer to step S101 and S102 in the first embodiment of the scanningmethod in a high-frequency system according to the embodiments of thepresent invention, and details are not described herein again.

In some feasible implementation manners, when scanning T regions in an Sregion by using a beam emitted by the base station, the base station mayalso add, to a beam signal, a synchronization sequence that is to besent to user equipment, and sends the synchronization sequence to theuser equipment. Specifically, in this embodiment of the presentinvention, a frame structure may be predefined. As shown in FIG. 2, inthe foregoing frame structure, each radio frame may include K1equal-sized radio subframes, each radio subframe may include K2equal-sized timeslots, and each timeslot may include K3 OFDM symbols,where K1, K2, and K3 are positive integers. Specifically, the basestation may insert multiple OFDM symbols into one downlink timeslot inone radio subframe in the frame structure, for sending thesynchronization sequence to the user equipment. A quantity of insertedOFDM symbols is equal to the quantity of T regions. In specificimplementation, an OFDM symbol includes multiple subcarriers in afrequency domain, and the base station may modulate a correspondingsequence symbol onto some specific subcarriers in the OFDM symbol, so asto insert the synchronization sequence into the OFDM symbol, and sendthe synchronization sequence to user equipment in a T region by usingthe OFDM symbol.

Further, in this embodiment of the present invention, thesynchronization sequence that is sent by the base station to the userequipment may include an ID of the beam that is emitted by the basestation to cover the T region. The T region (assumably T1) covered bythe beam is a T region in which the user equipment is located.Specifically, the ID of the beam may include a cell sequence C_ID, asector sequence SEC_ID, a space sequence S_ID, and a time sequence T_ID.The T_ID is an ID corresponding to T1, the S_ID is an ID of an S region(assumably S6) in which T1 is located, the SEC_ID is an ID of a sector(assumably a sector 1) in which S6 is located, and the C_ID is an ID ofa cell in which the sector 1 is located.

In some feasible implementation manners, after the base station pollsand covers all T regions in each S region in a time-division manner andsends the synchronization sequence to user equipment in each of the Tregions by using the frame structure, the user equipment may emit anarrow beam to perform scanning and receive the beam signal transmittedby the base station. After receiving the beam signal sent by the basestation, the user equipment may obtain the synchronization sequence fromthe beam signal and further feed back a corresponding sequence accordingto the obtained synchronization sequence. After receiving the sequencesent by the user equipment, the base station may determine a location ofthe user equipment, to confirm that scanning for the user equipment iscompleted.

In this embodiment of the present invention, a base station may evenly(or unevenly) divide a to-be-scanned sector into multiple S regionsaccording to a predefined S region division rule and divide each Sregion into multiple T regions according to a predefined T regiondivision rule, and further poll all T regions in each S region in atime-division manner. In addition, the base station may send asynchronization sequence to user equipment in the T region by using apreset frame structure, and determine a location of the user equipmentaccording to a sequence that is fed back by the user equipment, so as toaccess the user equipment. In this embodiment of the present invention,when multiple beams are used, a single beam may be used to poll all Tregions in a time-division manner, which effectively improves a cellcoverage rate under a beam freedom restricted condition, improves userexperience in using high-frequency narrow beams to implement cell-widecoverage, and reduces costs for cell-wide coverage.

Refer to FIG. 11, which is a schematic flowchart of a third embodimentof a scanning method in a high-frequency system according to theembodiments of the present invention. The scanning method described inthis embodiment includes the following steps:

S301. User equipment emits a beam to perform beam signal scanning and toreceive beam signals transmitted by a base station.

In some feasible implementation manners, the user equipment may emit anarrow beam to perform scanning, to align with a beam emitted by thebase station. The user equipment does not know a specific location ofthe base station, and therefore, the user equipment needs to performrotational scanning in an entire space range by using the beam emittedby the user equipment. A size of the entire range that the userequipment needs to scan may be predefined. When the beam emitted by theuser equipment (also referred to as a receive beam) is perfectly alignedwith the beam emitted by the base station (also referred to as atransmit beam), signal power received by the user equipment is thehighest, which means that when the receive beam of the user equipment isnot aligned with the transmit beam of the base station, signal powerreceived by the user equipment is lower, which does not help signaldemodulation. When the receive beam of the user equipment is perfectlyaligned with the transmit beam of the base station, the signal powerreceived by the user equipment is the highest, and information such asthe synchronization sequence may further be obtained from the transmitbeam of the base station. In specific implementation, a rotational scancycle of the beam emitted the user equipment needs to be greater than orequal to a scan cycle of the base station, to better find a beam that isemitted by the base station and that matches the beam. When the beam ofthe user equipment performs scanning, a beam direction may be changedonce at the end of each beam switching cycle until all-around beamscanning is completed. Specifically, the switching cycle may be a timethat a beam emitted by the user equipment stays in one scan direction.

S302. The user equipment obtains synchronization sequences from the beamsignals, and correlates all the synchronization sequences.

S303. The user equipment selects a synchronization sequence whosecorrelation peak value is the largest among correlation peak values ofall the synchronization sequences, and sets a beam corresponding to thesynchronization sequence as a serving beam.

In some feasible implementation manners, after obtaining thesynchronization sequences from the transmit beams of the base station,the user equipment may correlate the synchronization sequences.Specifically, in this embodiment of the present invention, each beamsignal sent by the base station carries a preset frame structure. In theframe structure, each radio frame includes K1 equal-sized radiosubframes, each radio subframe includes K2 equal-sized timeslots, andeach timeslot includes K3 OFDM symbols, as shown in FIG. 2, where K1,K2, and K3 are positive integers, and magnitudes of K1, K2, and K3 maybe defined according to an actual situation, which are not limited inthis embodiment of the present invention. The synchronization sequencesent by the base station is carried in OFDM symbols in the framestructure. The user equipment may learn, from the beam signaltransmitted by the base station, a frame structure that is used by thebase station to send the synchronization sequence, and obtain thesynchronization sequence from the OFDM symbols in the frame structure,and may further obtain the ID of the beam from the OFDM symbols, wherethe synchronization sequence is corresponding to the ID of the beam inthe OFDM symbols. Specifically, the ID of the waveform described in thisembodiment of the present invention may include a cell sequence C_ID, asector sequence SEC_ID, a space sequence S_ID, a time sequence T_ID, andso on. The T_ID is an ID corresponding to a T region (assumably T1) inwhich the user equipment is located when the base station sends thesynchronization sequence to the user equipment, the S_ID is an ID of anS region (assumably S6) in which T1 is located, the SEC_ID is an ID of asector (assumably a sector 1) in which S6 is located, and the C_ID is anID of a cell in which the sector 1 is located.

In some feasible implementation manners, because a cell in which theuser equipment is located may be covered by multiple base stations, theuser equipment may receive multiple beam signals from multiple cells.Therefore, the user equipment needs to select, from the beam signalstransmitted by the base stations, an optimal beam to be a serving beamfor the user equipment. In this embodiment of the present invention, theoptimal beam is a beam that matches the beam emitted by the userequipment, and the matching beam may be specifically a pair of beamswhose correlation peak values are the largest. In specificimplementation, after obtaining the synchronization sequences from thebeam signals transmitted by the base station, the user equipment maycorrelate all synchronization sequences that are transmitted by all thebase stations, to obtain a beam whose correlation peak value relative tothe beam emitted by the user equipment is the largest. Specifically, theuser equipment may obtain, from an OFDM symbol of each beam signal, anID of a beam corresponding to each synchronization sequence, andsequentially correlate a C_ID, a SEC_ID, an S_ID, and a T_ID that are inthe ID of the beam; select, according to a correlation result, asynchronization sequence whose correlation peak value is the largest,and set a beam corresponding to the synchronization sequence as theserving beam for the user equipment. An ID of the beam is an optimal ID.Specifically, the beam direction of the beam emitted by the userequipment changes once at the end of each switching cycle, andtherefore, after obtaining a serving beam in one switching cycle, whenthe beam of the user equipment enters a next switching cycle to performscanning, the user equipment may obtain a serving beam for the nextswitching cycle. By analogy, when a scan cycle of the user equipmentends, the user equipment may obtain multiple serving beams, and furthermay sort optimal IDs corresponding to all the serving beams, and selectone optimal ID group as an ID of a final serving beam for the userequipment.

S304. The user equipment inserts a sequence corresponding to an ID ofthe serving beam into a specified orthogonal frequency divisionmultiplexing OFDM symbol, and feeds back the sequence corresponding tothe ID of the serving beam to the base station.

In some feasible implementation manners, after selecting the servingbeam, the user equipment may feed back, to the base station, the ID ofthe serving beam including the C_DI, the SEC_ID, the S_ID, and the T_ID,to finally complete synchronization scanning in the high-frequencysystem. In specific implementation, the user equipment may select, fromOFDM symbols in an uplink timeslot, the OFDM symbol corresponding to theT_ID of the serving beam, insert sequences corresponding to the C_DI,SEC_ID, and S_ID of the serving beam into the OFDM symbol, and feed backthe sequence corresponding to the ID of the serving beam to the basestation by using the uplink timeslot. That is, an order of uplinkfeedback OFDM symbols in the uplink timeslot stays the same as an orderof downlink synchronization OFDM symbols in a downlink timeslot. In thiscase, the user equipment does not need to feed back the T_ID of theserving beam, and when receiving the ID of the serving beam that is fedback by the user equipment, the base station may determine the T_ID ofthe serving beam according to a location of an OFDM that is used to feedback the beam ID. In the foregoing feedback manner, the user equipmentneeds to select, from OFDM symbols in the uplink timeslot, the OFDMsymbol corresponding to the T_ID of the serving beam to be the OFDM thatis used to feed back the beam ID, and does not need to feed back asequence corresponding to the T_ID of the serving beam, which can reducefeedback sequences. For example, if an optimal ID corresponding to theserving beam that is selected by the user equipment is C_ID=1, SEC_ID=3,S_ID=5, and T_ID=8, sequences respectively corresponding to the C_ID=1,SEC_ID=3, and S_ID=5 may be inserted into a T8 OFDM symbol in the uplinkfeedback timeslot, and there is no need to feed back a sequencecorresponding to the T_ID to the base station. In specificimplementation, the sequences, described in this embodiment of thepresent invention, which are corresponding to the C_ID, SEC_ID, and S_IDand which are fed back by the user equipment are all orthogonalsequences, and the orthogonal sequences may be preset.

In some feasible implementation manners, the user equipment may furtherdefine an OFDM symbol in an uplink timeslot in advance. This OFDM symbolis used to feed back the ID of the serving beam to the base station,that is, the user equipment does not need to make a selection from allthe OFDMs in the uplink timeslot. After selecting the serving beam, theuser equipment may insert sequences corresponding to the C_ID, SEC_ID,S_ID, and T_ID of the serving beam into the predefined OFDM symbol, andfeed back the sequence corresponding to the ID of the serving beam tothe base station by using the predefined OFDM symbol in the uplinktimeslot. For example, if an optimal ID corresponding to the servingbeam that is selected by the user equipment is C_ID=1, SEC_ID=3, S_ID=5,and T_ID=8, sequences respectively corresponding to the C_ID=1,SEC_ID=3, S_ID=5, and T_ID=8 may be inserted into the predefined OFDMsymbol (for example, a second OFDM symbol) in the uplink feedbacktimeslot. That is, the user equipment does not need to select an OFDMsymbol from all the OFDM symbols to be an OFDM symbol that is used tofeed back the ID of the serving beam, but needs to feed back thesequence corresponding to the T_ID to the base station. In specificimplementation, the sequences, described in this embodiment of thepresent invention, which are corresponding to the C_ID, SEC_ID, S_ID,and T_ID and which are fed back by the user equipment are all orthogonalsequences, and the orthogonal sequences may be preset.

In this embodiment of the present invention, user equipment may obtainsynchronization sequences from beam signals transmitted by a basestation, and select a beam corresponding to an optimal ID to be aserving beam by means of sequence correlation, and may further feed backthe ID of the serving beam to the base station, to completesynchronization scanning in a high-frequency system. When feeding backthe ID of the serving beam to the base station, the user equipment mayperform the feedback in an OFDM symbol that is determined according tothe ID of the serving beam, or may perform the feedback in a predefinedOFDM symbol. This diversifies feedback manners, and improves userexperience in synchronization scanning.

The scanning method in a high-frequency system disclosed in thisembodiment of the present invention may be applied to a base station oruser equipment, and may be specifically implemented by a hardware modulesuch as a receiver, a processor, or a transmitter in the base station orthe user equipment. In an implementation process, the steps in themethod may be completed by a hardware integrated logic circuit orsoftware instructions in the receiver, transmitter, or processor. Theprocessor may be a general purpose processor, a digital signalprocessor, an application-specific integrated circuit, a fieldprogrammable gate array or other programmable logic device, a discretegate or transistor logic device, or a discrete hardware component, andis capable of implementing or executing the methods, steps, and logicalblock diagrams disclosed in the embodiments of the present invention.The general purpose processor may be a microprocessor, any conventionalprocessor, or the like. Steps of the methods disclosed with reference tothe embodiments of the present invention may be directly executed andcompleted by means of a hardware processor, or may be executed andcompleted by using a combination of hardware and software modules in theprocessor. The software module may be located in a mature storage mediumin the field, such as a random access memory, a flash memory, aread-only memory, a programmable read-only memory, anelectrically-erasable programmable memory, or a register.

It should be understood that “one embodiment” or “an embodiment”mentioned throughout this specification means that specificcharacteristics, structures, or features related to the embodiments areincluded in at least one embodiment of the present invention. Therefore,“in one embodiment” or “in an embodiment” that appears here and there inthe whole specification does not necessarily refer to a same embodiment.In addition, these specific characteristics, structures, or features maybe combined in one or more embodiments in any appropriate manner.Sequence numbers of the foregoing processes do not mean executionsequences in the embodiments of the present invention. The executionsequences of the processes should be determined according to functionsand internal logic of the processes, and should not be construed as anylimitation on the implementation processes of the embodiments of thepresent invention.

It should be understood that in the embodiments of the presentinvention, “B corresponding to A” means that B is associated with A andthat B can be determined according to A. It should also be understoodthat determining B according to A does not mean determining B accordingto only A, but determining B according to A and/or other information.

A person of ordinary skill in the art may be aware that, in combinationwith the examples described in the embodiments disclosed in thisspecification, units and algorithm steps may be implemented byelectronic hardware, computer software, or a combination thereof. Toclearly describe the interchangeability between the hardware and thesoftware, the foregoing has generally described compositions and stepsof each example according to functions. Whether the functions areperformed by hardware or software depends on particular applications anddesign constraint conditions of the technical solutions. A personskilled in the art may use different methods to implement the describedfunctions for each particular application, but it should not beconsidered that the implementation goes beyond the scope of the presentinvention.

It may be clearly understood by a person skilled in the art that, forthe purpose of convenient and brief description, for a detailed workingprocess of the foregoing base station, device, and module, refer to acorresponding process in the foregoing method embodiments, and detailsare not described herein again.

In the several embodiments provided in the present application, itshould be understood that the disclosed apparatus and method may beimplemented in other manners. For example, the described apparatusembodiments are merely exemplary. For example, the module division ismerely logical function division and may be other division in actualimplementation. For example, a plurality of modules or components may becombined or integrated into another system, or some features may beignored or not performed. In addition, the displayed or discussed mutualcouplings or direct couplings or communication connections may beimplemented by using some interfaces. The indirect couplings orcommunication connections between the apparatuses or units may beimplemented in electronic, mechanical, or other forms.

In addition, functional units (or functional modules) in the embodimentsof the present invention may be integrated into one processing unit, oreach of the units may exist alone physically, or two or more units areintegrated into one unit. The integrated unit may be implemented in aform of hardware, or may be implemented in a form of a softwarefunctional unit.

With descriptions of the foregoing embodiments, a person skilled in theart may clearly understand that the present invention may be implementedby hardware, firmware or a combination thereof. When the presentinvention is implemented by software, the foregoing functions may bestored in a computer-readable medium or transmitted as one or moreinstructions or code in the computer-readable medium. Thecomputer-readable medium includes a computer storage medium and acommunications medium, where the communications medium includes anymedium that enables a computer program to be transmitted from one placeto another. The storage medium may be any available medium accessible toa computer. The following provides an example but does not impose alimitation: The computer-readable medium may include a RAM, a ROM, anEEPROM, a CD-ROM, or another optical disc storage or disk storagemedium, or another magnetic storage device, or any other medium that cancarry or store expected program code in a form of an instruction or adata structure and can be accessed by a computer. In addition, anyconnection may be appropriately defined as a computer-readable medium.For example, if software is transmitted from a website, a server oranother remote source by using a coaxial cable, an optical fiber/cable,a twisted pair, a digital STA line (DSL) or wireless technologies suchas infrared ray, radio and microwave, the coaxial cable, opticalfiber/cable, twisted pair, DSL or wireless technologies such as infraredray, radio and microwave are included in a definition of a medium towhich they belong. For example, a disk and disc used by the presentinvention includes a compact disc (CD), a laser disc, an optical disc, adigital versatile disc (DVD), a floppy disk and a Blu-ray disc, wherethe disk generally copies data by a magnetic means, and the disc copiesdata optically by a laser means. The foregoing combination should alsobe included in the protection scope of the computer-readable medium.

In summary, what is described above is merely exemplary embodiments ofthe technical solutions of the present invention, but is not intended tolimit the protection scope of the present invention. Any modification,equivalent replacement, or improvement made without departing from thespirit and principle of the present invention shall fall within theprotection scope of the present invention.

What is claimed is:
 1. A base station, comprising: a processor,configured to use a single beam for each space (S) region in ato-be-scanned sector of a cell to poll or cover all time (T) regions inthe S region in a time-division manner; a transmitter, configured tosend, using a preset frame structure, a synchronization sequence that isobtained by the processor to user equipment in the T regions, whereinthe preset frame structure is carried in a beam signal; and a receiver,configured to receive a sequence that is fed back by the user equipment;wherein the processor is further configured to determine a location ofthe user equipment according to the received sequence, and to determine,according to the location of the user equipment, a serving beam for thebase station to communicate with the user equipment, and to confirm thatscanning for the user equipment is completed.
 2. The base stationaccording to claim 1, wherein the processor is further configured to:divide the to-be-scanned sector of the cell into a plurality of Sregions according to a predefined S region division rule, and divideeach of the S regions into a plurality of T regions according to apreset T region division rule.
 3. The base station according to claim 2,wherein the processor is further configured to: determine, according toa quantity of beams emitted by the base station, a quantity M of Sregions resulting from division of the to-be-scanned sector, whereineach of the S regions corresponds to one beam, and M is equal to thequantity of beams; and divide, according to the predefined S regiondivision rule, the to-be-scanned sector into M equal-sized S regions, orM S regions whose sizes correspond to widths of the corresponding beams.4. The base station according to claim 2, wherein the processor isfurther configured to: determine, according to a beam width of a beamemitted by the base station and a size of the S region, a quantity N ofT regions resulting from division of the S region; and divide each ofthe S regions into N T regions in the same division order or a differentdivision order according to the T region division rule.
 5. The basestation according to claim 1, wherein the transmitter is furtherconfigured to: insert M orthogonal frequency division multiplexing(OFDM) symbols into one downlink timeslot in one radio subframe in theframe structure, insert the synchronization sequence into the OFDMsymbols, and send the synchronization sequence to the user equipment inthe T region using OFDM.
 6. The base station according to claim 5,wherein the synchronization sequence comprises a sequence ID of the beamthat is emitted by the base station to scan the T region; and the ID ofthe beam comprises a cell sequence (C_ID), a sector sequence (SEC_ID), aspace sequence (S_ID), and a time sequence (T_ID).
 7. User equipment,comprising: a receiver, configured to emit a beam to perform beam signalscanning and receive beam signals transmitted by a base station; aprocessor, configured to: obtain synchronization sequences from the beamsignals received by the receiver, and correlate all the obtainedsynchronization sequences; select a synchronization sequence whosecorrelation peak value is the largest among correlation peak values ofall the obtained synchronization sequences, and set a beam correspondingto the synchronization sequence as a serving beam; and insert a sequencecorresponding to an ID of the serving beam into a specified orthogonalfrequency division multiplexing (OFDM) symbol; and a transmitter,configured to feed back the sequence corresponding to the ID of theserving beam to the base station.
 8. The user equipment according toclaim 7, wherein OFDM symbols in frame structures of the beam signalscomprise an ID of the respective beam, and the IDs of the beams comprisea cell sequence (C_ID), a sector sequence (SEC_ID), a space sequence(S_ID), and a time sequence (T_ID).
 9. The user equipment according toclaim 8, wherein the synchronization sequence is carried in OFDM symbolsand the synchronization sequences correspond to respective IDs of thereceived beams; and wherein the processor is further configured toobtain the IDs of the beams corresponding to the synchronizationsequences from the OFDM symbols in the beam signals, and to sequentiallycorrelate the C_IDs, SEC_IDs, S_IDs, and T_IDs in the IDs of the beams.10. The user equipment according to claim 9, wherein: the processor isfurther configured to: select an OFDM symbol corresponding to a T_ID ofthe serving beam from OFDM symbols in an uplink timeslot; and insertsequences corresponding to a C_ID, a SEC_ID, and an S_ID of the servingbeam into the selected OFDM symbol; and wherein the transmitter isfurther configured to: feed back the sequence corresponding to the ID ofthe serving beam to the base station by using the uplink timeslot. 11.The user equipment according to claim 10, wherein the sequencescorresponding to the C_ID, SEC_ID, S_ID, and T_ID of the serving beamare all predefined orthogonal sequences.
 12. The user equipmentaccording to claim 10, wherein: the processor is further configured to:predefine an OFDM symbol in the uplink timeslot; and insert sequencescorresponding to a C_ID, a SEC_ID, an S_ID and a T_ID of the servingbeam into the predefined OFDM symbol; and the transmitter is furtherconfigured to: feed back the sequence corresponding to the ID of theserving beam to the base station by using the uplink timeslot.
 13. Amethod, comprising: using, by a base station, a single beam for eachspace (S) region in a to-be-scanned sector of a cell to poll or coverall time (T) regions in the S region in a time-division manner, andsending a synchronization sequence to user equipment in the T regions byusing a preset frame structure, wherein the frame structure is carriedin a beam signal; and receiving, by the base station, a sequence that isfed back by the user equipment, determining a location of the userequipment according to the sequence, and determining, according to thelocation of the user equipment, a serving beam for the base station tocommunicate with the user equipment, and to confirm that scanning forthe user equipment is completed.
 14. The method according to claim 13,wherein before using, by the base station, the single beam for eachspace S region in a to-be-scanned sector of a cell to poll or cover alltime T regions in the S region in a time-division manner, the methodfurther comprises: dividing the to-be-scanned sector of the cell into aplurality of S regions according to a predefined S region division rule,and dividing each of the S regions into a plurality of T regionsaccording to a preset T region division rule.
 15. The method accordingto claim 14, wherein dividing the to-be-scanned sector of the cell intothe plurality of S regions according to the predefined S region divisionrule comprises: determining, according to a quantity of beams emitted bythe base station, a quantity M of S regions resulting from division ofthe to-be-scanned sector, wherein each of the S regions corresponds toone beam, and M is equal to the quantity of beams; and dividing,according to the predefined S region division rule, the to-be-scannedsector into M equal-sized S regions, or M S regions whose sizescorresponding to widths of the beams.
 16. The method according to claim14, wherein dividing each of the S regions into the plurality of Tregions according to the preset T region division rule comprises:determining, according to a beam width of a beam emitted by the basestation and a size of the S region, a quantity N of T regions resultingfrom division of the S region; and dividing each of the S regions into NT regions in the same division order or a different division orderaccording to the T region division rule.
 17. The method according toclaim 13, wherein sending the synchronization sequence to user equipmentin the T region using the preset frame structure comprises: inserting Morthogonal frequency division multiplexing (OFDM) symbols into onedownlink timeslot in one radio subframe in the frame structure,inserting the synchronization sequence into the OFDM symbols, andsending the synchronization sequence to the user equipment in the Tregion using the OFDM.
 18. The method according to claim 17, wherein thesynchronization sequence comprises a sequence ID of the beam that isemitted by the base station to scan the T region; and the ID of the beamcomprises a cell sequence C_ID, a sector sequence SEC_ID, a spacesequence S_ID, and a time sequence T_ID.
 19. A method, comprising:emitting, by user equipment, a beam to perform beam signal scanning andreceive beam signals transmitted by a base station; obtaining, by theuser equipment, synchronization sequences from the beam signals, andcorrelating all the synchronization sequences; selecting, by the userequipment, a synchronization sequence whose correlation peak value isthe largest among correlation peak values of all the synchronizationsequences, and setting a beam corresponding to the synchronizationsequence as a serving beam; and inserting, by the user equipment, asequence corresponding to an ID of the serving beam into a specifiedorthogonal frequency division multiplexing (OFDM) symbol, and feedingback the sequence corresponding to the ID of the serving beam to thebase station.
 20. The method according to claim 19, wherein OFDM symbolsin frame structures of the beam signals comprise IDs of the beams, andthe IDs of the beams comprise a cell sequence (C_ID), a sector sequence(SEC_ID), a space sequence (S_ID), and a time sequence (T_ID).
 21. Themethod according to claim 20, wherein the synchronization sequences arecarried in the OFDM symbols and the synchronization sequences correspondto the IDs of the beams in the OFDM symbols; and wherein obtaining, bythe user equipment, synchronization sequences from the beam signals, andcorrelating all the synchronization sequences comprises: obtaining, bythe user equipment, the IDs of the beams corresponding to thesynchronization sequences from the OFDM symbols in the beam signals, andsequentially correlating the C_IDs, SEC_IDs, S_IsD, and T_IDs in the IDsof the beams.
 22. The method according to claim 21, wherein inserting,by the user equipment, the sequence corresponding to the ID of theserving beam into the specified OFDM symbol, and feeding back thesequence corresponding to the ID of the serving beam to the base stationcomprises: selecting, by the user equipment, an OFDM symbolcorresponding to a T_ID of the serving beam from OFDM symbols in anuplink timeslot; and inserting, by the user equipment, sequencescorresponding to a C_ID, a SEC_ID, and an S_ID of the serving beam intothe selected OFDM symbol, and feeding back the sequence corresponding tothe ID of the serving beam to the base station using the uplinktimeslot.
 23. The method according to claim 21, wherein inserting, bythe user equipment, the sequence corresponding to the ID of the servingbeam into the specified OFDM symbol, and feeding back the sequencecorresponding to the ID of the serving beam to the base stationcomprises: predefining, by the user equipment, an OFDM symbol in anuplink timeslot; and inserting, by the user equipment, sequencescorresponding to a C_ID, a SEC_ID, an S_ID, and a T_ID of the servingbeam into the predefined OFDM symbol, and feeding back the sequencecorresponding to the ID of the serving beam to the base station usingthe uplink timeslot.
 24. The method according to claim 20, wherein thesequences corresponding to the C_ID, SEC_ID, S_ID, and T_ID of theserving beam are all predefined orthogonal sequences.